import java.util.Scanner;

public class java14 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入数字:");
        int num1 = scanner.nextInt();
        for (int i=0;i<=num1;i++)
        {
            if(i%2==0)
                System.out.print(" "+i);
        }
    }
}
